Sailor Piece’s latest update doesn’t just add new content—it introduces one of the strongest melee weapons in the game right now: Moon Slayer. With massive burst damage, a powerful F move, and materials tied to the new boss, this weapon is clearly designed to dominate boss farming.
But unlocking it isn’t simple.
From farming rare drops on Lawless Island to repeatedly summoning the Moon Slayer boss, getting this weapon requires a full grind route. Here’s the fastest way to unlock Moon Slayer, how to get its F move, and whether it’s actually worth the effort.
Moon Slayer Requirements (All Materials)
To craft Moon Slayer, go to Boss Island and find the Moon Slayer NPC.
You’ll need:
- Six-Eyed Demon Title
- 37,500 Gems
- 1 Moon Crest
- 4 Crescent Shards
- 9 Lunar Essence
- 16 Demon Remnant
- 25 Upper Seals
Step 1: Farm Upper Seals (Lawless Island)
This is where your grind starts.
How to get Upper Seals:
- Go to Lawless Island
- Defeat NPCs
- Drops are low chance
Important:
You’ll need:
- 25 for crafting
- 85 more for F move later
So don’t stop early—farm a large stack.
Step 2: Farm Moon Slayer Boss (Boss Island)
Once you have Upper Seals:
Boss Requirements:
- 750 Gems
- 1 Upper Seal
What the boss drops:
- Six-Eyed Demon Title
- Moon Crest
- Crescent Shards
- Lunar Essence
- Demon Remnant
Six-Eyed Demon Title
This is the most important drop.
Why it’s insane:
- +85% Damage Buff
- 155 Pity System (guaranteed eventually)
Even outside crafting, this alone is a huge upgrade.
Step 3: Craft Moon Slayer
Once you have all materials:
- Go back to Moon Slayer NPC
- Craft the melee
At this point, you already have one of the strongest weapons in the game.
How To Unlock Moon Slayer F Move
To fully complete the weapon, you need the F move.
Go to Moon Slayer Master NPC (Boss Island)
Requirements:
- Moon Slayer Melee
- Upper Clan
- 2 Moon Crest
- 10 Crescent Shards
- 85 Upper Seals
Upper Clan (Required for F Move)
This is a new Legendary Clan.
Stats:
- +40% Damage
- +50% Max HP
- +12% Melee Damage
- +12% Luck
Important:
- You must roll for it
- Save clan rerolls before starting grind
Moon Slayer Damage Breakdown
Here’s how strong it actually is:
Z Skill
- ~2 Billion Damage
- Moves your character
- Better for bosses than mobs
X Skill
- ~2.2 Billion Damage
- No movement → cleaner usage
- More consistent in fights
C Skill
- 5+ Billion Damage
- Large AoE
- Best for mob clearing
V Skill
- 10+ Billion Damage
- High burst
- Long cooldown
F Move (Mastery)
- 15+ Billion Damage
- Extremely high burst
- Best boss-killing skill